Liquefied gas filler and eduction device



Jan. 30, 1968 H. N. SHAW 3,366,139

LIQUEFIED GAS FILLER AND EDUCTION DEVICE Filed Sept. 4, 1964 7 Sheets-Sheet 1 FIG.4

FIG. I

INVENTOR.

HARRY N. SHAW 13,. 30, 1968 H. N. SHAW 3,366,139

LIQUEFIED' GAS FILLER AND EDUCTION DEVICE Filed Sept. 4, 1964 7 Sheets-Sheet 2 I NVENTOR.

HARRY N. SHAW Jan. 30, 1968 H. N. SHAW 3,366,139

LIQUEFIED GAS FILLER AND EDUCTION DEVICE F'iled Sept. 4, 1964 7 Sheets-$heet "I 32 a I (:1 9 l6 2' l7 24 20 3: I I as 27 22 1 as I 29 l I 37\\ 3 9 4o HI I so 4 n9 J 46 t p 7 8| 72 02 I 93 E I04 f i me, 06 I00 INVENTOR HARRY N. SHAW FIG. 2

Arm

Jan. 30, 1968 H. N. SHAW 3,366,139

LIQUEFIED GAS FILLER AND EDUCTION DEVICE Filed Sept. 4, 1964 7 Sheets-Sheet 4 FIGZA INVENTOR.

HARRY N. SHAW Jan. 30, 1968 H. N. SHAW LIQUEF'IED GAS FILLER AND EDUCTION DEVICE 7 Sheets-Sheet 5 Filed Sept. 4, 1964 R W T. O M T T A N S E V N WY 7 R 7 R A H 2 H Y B o. M 5 B 2 G F 9 8 3 a 7 0 v d 2 9 b b 9 2 b 5 m w a u 3 l l m Jan. 30, 1968 H. N. SHAW 3,366,139

LIQUEFIED GAS FILLER AND EDUCTION DEVICE Filed Sept. 4, 1964 7 Shets-Sheet 6 FIG. 2C

INVENTOR H ARRY N. SHAW H. N. SHAW Jan. 30, 1968 LIQUEFIED GAS FILLER AND EDUCTION DEVICE 7 SheetsSheet 7 Filed Sept. 4, 1964 m T. m V m HARRY N. SHAW United States Patent 3,366,139 LIQUEFIED GAS FILLER AND EDUCTION DEVICE Harry N. Shaw, Chicago, 11]., assignor to The Bastian- Blessing Company, Chicago, Ill., a corporation of Illinois Continuation-impart of application Ser. No. 276,903, Apr. 30, 1963. This application Sept. 4, 1964, Ser. No. 394,5?0

16 Claims. (Cl. 137565) This application is a continuation-in-part of my copending application Ser. No. 276,903, filed Apr. 30, 1963, 110W Patent No. 3,175,579 reference and incorporation of which is hereby made.

This invention relates in general to fluid filling and emptying systems for handling liquefied gas in bulk storage and transport containers which are generally of a cylindrical shape, and more particularly to a filler-eduction safety cut-off valve construction which provides all the safety advantages of excess flow valves without some of their disadvantages of normal openness and large pressure drops, and also includes the safety advantages of an overriding positive shut-off valve which is located protectively inside the container yet can be remotely controlled both manually and automatically to close or open automatically during the filling or dispensing of gas in its liquid phase as part of a closed system in which operating pressures are present or are developed with the liquefied gas being handled.

For many years the manufactures and users of liquefied petroleum gas handling equipment have been concerned about the problems arising with starvation on the inlet side of their eduction pumps when high capacity pumping is desired for emptying a storage container with sufficient rapidity for such to be economical.

Where water remains liquid at the intake of a pump when cavitation conditions might develop, liquefied gas presents an aggravated problem. Liquefied gas such as propane or butane have low boiling points and at normal atmospheric temperatures they have sufficient sensible heat available to furnish substantial amounts of latent heat of vaporization, Therefore, under liquid solid conditions liquefied gas is quite sensitive to vaporization with drops in pressure that may be induced in dispensing conduits ahead of pumps. A slight drop of pressure below the vapor pressure even before lower cavitation pressures are reached causes vaporization that forms gas pockets. Such pockets as well as cavitation at the pump blades is harmful to the pump.

Now, if a positive hydraulic head can be maintained upon liquefied gas at the pump inlet, Le, a pressure above the vapor pressure in the tank, the pumping conditions can be greatly improved since the pump would not be required to draw liquefied gas from the container to which it is connected under conditions causing vaporization and cavitation. However, the excess flow valves now provided for safety purposes in eduction conduits leading to pump intakes depend upon a substantial pressure differential to operate. Such differentials have to be built into the design of excess flow valves notwithstanding the fact that the required differential drop across the excess flow valve is a liability at high pumping rates. Slow pumps have to be used because pumps fast enough to be economical often exceed the flow characteristics for which the excess flow valves are designed and the valve repeatedly snaps closed. This generally occurs irrespective of the head pressure above the valve.

However, since the downstream rate of flow is what influences the pressure drop differential occurring at the excess flow valve, it has been noted that if the downstream flow rate is kept constant and within the capacity of the valve the pressure drop differential increases as the tank fififihiiih Patented Jan. 30, 1968 approaches empty. The flow is gradually being starved at the valve as long as it is open because of a decreasing head pressure at the valve inlet. Thus, head pressure loses its helpfulness as soon as it becomes less than the pressure drop across the valve. The greater that the pressure drop across the valve exceeds the hydraulic head, the greater will be the tendency for the pump intake to cause vaporization and cavitation.

For instance, assume two valves rated for identical installation with one valve designed for a one pound pressure drop differential to close as an excess flow valve while the other valve designed for shut-oft has a pressure drop of only one quarter pound for the same rate of flow of approximately gallons per minute. It Will be observed that approximately a four foot hydraulic head, or more, of liquefied gas is required to make up for the one pound pressure drop to maintain a liquid solid condition at the pump intake without vaporization dangers, whereas, with the other valve anything over a one foot head will maintain a liquid solid condition at the pump intake.

Thus, with horizontally disposed cylindrical tanks large enough to provide an initial head over four feet such as a tank five or six feet in diameter, the desired head pressure is lacking except for a very small amount of liquid dispensed before the hydraulic head rapidly falls below the four foot mark due to the curvature of the tank. Thereafter vaporization becomes an increasing danger with the pressure between the valve and pump increasingly below the vapor pressure and there still would be a major portion of liquid left to be educted. In brief, the level of the liquid would drop quickly down to the four foot depth and after that very slowly around the half full level and thereafter progressively more rapidly as the bottom is approached.

Obviously, this problem is further aggravated where two cylindrical tanks small enough to be mounted side by side in limited space as on a vehicle are required in order to transport liquefied gases having two different vapor pressures.

Although air pressure can be added to assist the diminishing hydraulic head, such pressure being additive to the vapor pressure, the eifective tank pressure would be intolerably high when full in order to have three quarters of a pound remaining to be effective as a supplement to the hydraulic head when only one foot of liquid remains in the tank. On the other hand, if the pressure drop across the valve is slight, such as one quarter of a pound, then only enough air need be added to assist the last foot of liquid in the container. Its additive pressure need be only two pounds above vapor pressure with the tank half full and approximately eight pounds when the tank is filled to the usual 10 percent outage. Thus, with a low pressure drop at the valve this mild assist pressure is quite tolerable. It is not too high for tank ratings and it is substantially unchanged by temperature, yet safely assists in providing an effective head much higher than the hydraulic head alone could provide with a full tank and a high rate of flow would not be confronted with a valve closure. However, for a remaining one foot hydraulic head with so little remaining volume in the tank yet to be educted the need for a hydraulic pressure assist is virtually eliminated by the present invention.

Moreover, comparatively speaking, where conventional filler-eduction excess flow check valves are designed to have as much pressure drop as can safely be possible yet interfere with pump capacity as little as possible, it is to be observed that the present invention is virtually open to full fiow with comparatively no pressure drop that materially affects the pump. Additionally, it is controlled to close automatically, instantly, with greater sensitivity to pressure drops caused by fluid escaping through small breaks ahead of or beyond the pump.

Accordingly, one of the object of the present invention is to provide a safety cut-off valve for performing excess flow valve functions where the drop of pressure across the valve itself is very slight and therefore, only a slight hydraulic head is needed to maintain a positive head pressure to maintain a liquid solid prime at the pump intake.

Another object of the invention is to provide a fillereduction valve with which a positive head pressure will be provided for the intake of the eduction pump throughout substantially all of the tank emptying pumping operation whereby operating factors without vaporization or cavitation are greatly improved for high volume pumps.

A further object of the invention is to provide a liquid eduction safety valve that is controlled manually to open and close and to close or be released to open either mechanically or hydraulically by application of pressures developed or present in the system with or without the pump running.

Another object of the invention is to provide a liquid filler-eduction valve that opens against the outflow of liquid from the tank by feed back of eduction pump output pressure to the valve actuating mechanism.

It is a further object of this invention to provide an improved, light, unitary, self-contained valve and pump apparatus secured to a transport tank which rapidly educts the fluid from the tank with full safety without reliance on external or excess fiow control valves.

A further object of the invention is to provide a safety cut-off valve responsive to nominal drops in pressure which may be used in dual tank installations in the dispensing of two liquefied gases having different vapor pressures with the use of a single high volume pump.

Another object of this invention is to provide an improved, fully automatic, internally mounted flow cut-off valve coupled with a high capacity pump which valve automatically assumes the closed position until the pump is started, thereby precluding over-the-road travel with an open valve yet can be opened manually if the pump fails to start.

A further object of this invention is to provide an improved valve internally mounted in a tank for fluid control having a visual indicator denoting whether the valve is in the open or closed position.

Another object of this invention is to provide an improved, fully automatic, internally mounted flow control valve coupled with a high capacity pump and valve arrangement of minimized weight to be carried beneath a bulk tank whereby the tank may be filled or drained with minimum time and expense.

The invention is further characterized by valve con struction which will keep the pump inlet primed with little or no leakage fro-m the tank in event the valve is broken off of the tank or becomes damaged.

Another object of this invention is to provide an improved liquid emptying and filling apparatus that is simple in design, rugged in construction, economical to manufacture, adaptable for mounting on existing tanks or new construction, completely self-contained to complete a fluid filling or eduction operation and provides maximum safety and fail-safe operational characteristics.

Still another object of this invention is to provide an improved, automatically operated flow valve, having locking means whereby the valve can be secured against opening by back pressure from a manifold and a similar valve operating from another compartment or container.

Further objects and advantages of the invention will be readily apparent from the following detailed description of a specific embodiment of the invention with references made to the accompanying drawings in which:

FIG. 1 is a fragmentary partially sectioned schematic view showing the valve control and system incorporating a pump and valve for a typical utilization of the invention;

FIG. 1A is a view similar to FIG. 1 showing a further embodiment of the invention for single tanks or the higher pressure tank of a double tank installation;

FIG. 2 is a fragmentary partially sectional side elevational view illustrating the draining and filling apparatus of this invention and the position of the component parts of the valve shown in FIG. 1 when in the closed position;

FIGS. 2A and 2C are enlarged sectional views similar to FIG. 2 showing the valve construction shown in FIG. 1A, with FIG. 2C being a further enlargement of the upper portion of the valve shown in FIGS. 1A and 2A;

FIG. 2B is a view similar to FIG. 2 showing a further embodiment of the invention for the lower pressure tank of a double tank installation referred in connection with FIG. 1A;

FIG. 3 is a partially sectioned bottom view of the draining and filling apparatus illustrating the relationship of certain components on the lower portion of the apparatus shown in FIG. 1;

FIG. 4 is a linear view of the locking and unlocking means showing the particular components over of rotation;

FIG. 4A is a diagrammatic showing of the arrangement of the embodiments shown in FIGS. 1A and 2-B in a double tank installation;

FIG. 5 is a fragmentary view similar to FIG. 2 showing a modification of the device shown therein; and

FIG. 5A is a view similar to FIG. 5 showing a modification thereof for use in all devices shown where atmospheric pressure is employed as reference pressure.

The invention is characterized by a liquid filler and eduction valve normally closed by a spring in the direction of outflow from a tank within which it is protectively mounted at the bottom thereof. Although the valve can be rotated as well as reciprocated with respect to its seat and the valve stem for manual control for positive closing, the valve stem in one embodiment is rotatably supported and extends outwardly through the wall of the tank where it can be manipulated to move the valve between two positions. In one position the valve is positively shut by a stationary cam rise and in the other it is released to open over a cam relief. For this purpose the stem is also rotatably mounted as received through a diaphragm which longitudinally displaces the valve stem to open the valve whenever the pressure on the lower side of the diaphragm is higher than that present on the upper side Whereas a balance of pressures on opposite sides either of high or low pressures permits the spring to close the valve. In the other embodiment instead of stem rotation with respect to a cam a radially movable latch arrangement snap engages a shoulder on the stem to lock it in closed position. In both instances manual action is required to release the stem for valve opening movement.

The upper diaphragm chamber may be supplied with pressure from two sources to close the valve, namely the pressure present in the valve, or the tank pressure. On the other hand the upper chamber can be vented to atmosphere for opening the valve. The lower diaphragm chamber may be supplied with the pump outlet pressure which is superior to both the valve outlet pressure and the tank pressure for opening the valve, or to either tank or valve outlet to open the valve when the upper chamber is vented to atmosphere. In either event the valve is closed by spring means whenever both chambers have equalized pressures or are vented to atmosphere or both. Provision is made for priming the pump before operation in that a bleed passage bypasses the valve or a passage through the valve is controlled by a normally open check valve.

Like numerals refer to like parts throughout the several embodiments and suffix letters indicate modifications thereof if significant.

Referring now to the drawings in further detail, a valve 1 is mounted at an opening 2 in the bottom of a tank 3 with its outlet 4 connected by conduit 5 to the inlet 6 of pump 7 which has an outlet 8. The valve 1 comprises a valve body 29 (FIGS. 1 and 2) defining a valve seat at 22 engaged by a valve head 19. The body has a cylindrical inverted cup-like cap 9 marginally threaded at 27 to a male coupling thread on the body 29 bordering a valve seat 22. At the top of the cap 9 a boss 13 is provided with a central bore 11 which reciprocably receives rotatably therein a stub shaft 14 having a cross head 16 therebelow supporting a shaft 21 that journals cam follower rollers 15 to follow an axial cam surface 23 on a cam ring 10' that bottoms on a shoulder 28 in the cap 9 and has a detent 32a at the top of the cam rise 32 (FIG. 4). In FIGS 1A, 2A and 2B the stub shaft is merely reciprocable and serves as a valve body 14a (FIGS. 1A and 2A) and 14b (FIG. 2B) for controlled movement of liquefied gas through the valve 19 under conditions described hereafter.

A compression spring 12 engages the crosshead 16 (FIG. 2) and urges it downwardly whereby the valve head 19 journalled on a stud 30 below the crosshead 16 is urged to close against the valve seat 22 through a bearing washer 17 made of a material having a low friction coefiicient. The lower end of the stud 39 is machined to provide a wrenching surface 25.

Below the valve seat 22 a main shaft or valve stem 37 is journalled in the body 29 for reciprocable movement (FIG. 3) as later described and has a wrenching socket 31 telescoping over the surface 25 as supported in engagement therewith by an external spring washer 18 resting on top a flanged collar 26 threaded to the valve head 19 to also hold the valve disc 20 in place. There preferably is very little end play between the shafts 14 and 37, consequently movement of the main shaft 37 operates with the stub shaft 14 as a unitary valve stem for the valve 19. The valve in turn is rotatably mounted on the stem so that stem can open and close the valve without rotation of the valve with respect to the valve seat. The valve disc 20 is thick enough that the resiliency thereof permits the rollers 15 to attain the detents 32a (FIG. 4) and hold them there.

Thus, when the cam rollers 15 are on the cam rise 32 in the detent 32a, the stem cannot be moved axially to open the valve, but when the rollers 15 are over the cam reliefs 35 the stem is free to open and close the valve, yet the cam rollers can be turned any time to mechanically force closure of the valve even from its open position. Openings 24 through the wall of the cap 9 perrrrit liquid to flow from the tank 3 to the valve seat 22 and preferably a screen filter 34 is installed over the openings a spaced distance therefrom to prevent solid particles from damaging the valve disc.

Just below the valve seat 22 the body 29 can be mounted in sealed relation in the opening 2 in the tank 3 either by a threaded joint 35 arrangement (FIG. 2) or as shown in FIG. 1 by a flange and bolt mounting 41. Flange mounting is preferred for ready orientation of the valve irrespective of thread tightening.

Below the tank mounting 41 the body is shaped generally as an elbow fitting with a right angle passage 60 therethrough and with the outside wall 42' thereof contoured and recessed to provide a diaphragm compartment 50 having a threaded opening 43 through the crown thereof disposed coaxial with the seat 22 and in communication with the passage 60. The shaft 37 is received through this opening as journalled in guided relation by a threaded collar 46 supporting a bearing member 47 which has small longitudinal interior grooves 45 facing the shaft to permit restricted communication between the passage 60 and compartment 50.

Closing the mouth of the compartment 50 is a diaphragm 52 clamped in place by a bonnet 70 held by bolts 71 and having an area exposed on the lower side appreciably greater than the area defined by the valve seat 22. The diaphragm 2 is apertured to receive the shaft 37 therethrough and is provided with a diaphragm collar 73 having an O-ring seal 76 engaging the shaft 37. The diaphragm is secured in sealed relation to the collar 73 by a washer 74 and nut 75 secured to the collar. The collar has a bleed orifice 53 (-FIG. 2) through it and the shaft has a shoulder 51 and a spring washer 72 which couples together the vertical movement of the diaphragm and shaft 37 to dispose the diaphragm in its lower position when the valve is closed. The bleed orifice 53 is omitted ing FIGS. 5 and 5A for purposes later described.

The bonnet 70 defines a chamber below the diaphragm 52 and has a central opening 97 receiving a collar threadedly therein for journalling the shaft 37 in a relationship sealed by a gasket 102. The collar extends beyond the bottom of the bonnet and into a circular cavity 98 provided in the bottom wall 99 where it loosely supports in threaded relationship a socket wrench member 193 having a handle 120 on it for actuation and a socket 160 slidably receiving the squared lower end 106 of the shaft 37 for rotating the shaft thereby.

The periphery of the socket member 1% is journalled in the circular cavity 98 and has a groove 96 therein provided with camming rollers 110 Which displace outwardly a pilot valve stem 104 that radially intersects the groove. The stem when displaced opens a normally closed valve 91 that is threaded into the side wall of the bonnet to vent the bonnet chamber 80 to atmosphere through passages 81 and 93 drilled in the wall and the stem 104, respectively. The valve 91 can be assembled and serviced by removal of a back cap 94. Whenever the valve 19 opens, the lower end of the stem 37 disappears within the socket member 103 to serve as an indicator that the valve 19 is open.

Lugs shown at A and B (FIG. 3) limit the movement of the handle to an angle of 90 and as shown in broken lines, the cam rollers 11d engage the relief valve stem 194 when the handle is passing from its open to its closed position against lug A. This engagement frees the relief valve to close at both limits of its movement. Thus, when the valve 19 is being closed, the vent valve 91 is momentarily opened to vent chamber 80 so that no hydraulic pressure can be built up in the chamber 86 that would oppose the diaphragm movement when the valve 19 is moved to its closed position, and then closed again so that no liquefied gas is lost to the atmosphere.

When the handle 120 is in open position, pressure can be supplied to or vented from the chamber 80 through any one of a number of nipple connections such as 112, 113 and 114. Connections not used are plugged.

The outlet end of the body 29 is threaded as at 139 to receive the conduit 5 leading to the intake 6 of a pump 7 having an output connection 8. It will be observed that the pump is connected and is designed to pump liquid. Accordingly, it is desirable that the intake of the pump be primed with liquid before it is started. The invention provides for several ways to do this. In FIGS. 1 and 2 it is through a conduit 36 drilled in the body 29 down to a threaded. opening 39 to take liquid from the tank. In FIGS. 1A and 2A it is through the valve 19.

The preferred way is to bottom drill the opening 39 into the passage 60 to provide a conduit 84 bypassing the valve 19 and threading a needle valve plug 40 into the opening to adjust for a continuous bleed of liquid from the tank to the passage 60 to keep the passage 6!) and pump 7 primed.

A connection 82 leads from the output side 8 of the pump 7 so that once the pump is started, the output pressure of the pump is eflfective in chamber 80 and opens the valve 19. However, in event there is a break in the pump output hose, the output pressure drops. Then the compartment 80 is no longer supplied with the pump output pressure which is above the pump intake pressure present in the upper compartment 50 and the diaphragm is quickly balanced on opposite sides through the bleed passage 53. Thereupon the spring 12 assisted with the outflow of liquid through the valve closes the valve 19 in seconds. Thus, a very slight drop in pump output pressure operates to close the valve, thereby providing a very sensitive but full flow safety shut-off valve arrangement.

It is desirable to provide a manual shutolf valve 83 in the connection 82 which is normally left open but when an emergency arises it can be closed to cut off the pump outlet pressure and accomplish the closing of the valve 19 with the same effect as though a break had occurred in the pump outlet 8.

In addition to the vent valve 91 at back cap 94, a safety line 135 (FIGS. 1 and 3) can be extended from one of the nipple connections 113 or 114 to run to an operators station or to other critical points around the tank where hand operated vent valves 101 may be located whereby the pressure in compartment 80 can be vented at any one of a number of stations to close the valve 19 and in this connection it is to be noted (FIG. 3) that only safety line connections 113 and 114 have bleed orifice elements 115 to limit the supply pressure when relieving through safety lines and to minimize pulsations of pump supply pressure. If desired a back flow check valve (not shown) can be used in the line 105 next to the nipple connection to prevent emptying the line 185 each time the vent valve 91 is actuated to vent chamber 80.

Referring now to the embodiment shown in FIGS. 1A and 2A, the valve stem 37a is reciprocably mounted in the body 29a and is rigidly secured to the diaphragm 52 by a nut 54 threaded to the stem to clamp the intervening diaphragm collar 73 solidly against the shoulder 51. The lower end of the stem 37a is drilled out and internally threaded as at 44 to receive an indicating stem 48 having an enlarged hexagonally contoured head 49 on the lower end defining an upwardly facing shoulder 55 movable within the cavity 98a and serving as a valve position indicator therebelow. The cavity is closed at the bottom by a cover plate 56 having a correspondingly sectionally contoured opening 57 mating with the head 49 to prevent rotation of the valve stem. A dirt stop is shown at 58.

Means for locking the stem against upward valve movement is provided including a locking ring 59 slidable within the cavity 93a in a direction crosswise to the stem 48. The ring is urged by a spring 61, as guided by a locking arm 62 threaded to it, to move into a position blocking the shoulder 55 against the upward movement. The locking arm 62 extends slidably through a spring retainer 63 for manipulation before the valve stem can move upwardly. An outward pull on the locking arm frees the valve for opening movement. A set screw assembly 64 is provided primarily for production testing of the valve.

fter installation it is backed off to permit the locking ring to function.

At its upper end the stem 37a is slidably mounted in the flanged collar 26 above which it projects. The projection portion is circumferentially grooved at 65 to receive a C washer 66 that hold it in place. The stem is free to move a further distance above the collar in a cavity 67 provided in the valve head 19:: for a purpose now to be described. Adequate clearances are provided for flow of fluid between the cavity 67 and the passage 60.

A conduit 68 coaxial with the stern 37a is provided in the valve head 19a and interconnects the cavity 67 and the tank 3. A normally open valve is disposed therein and includes a piston 69 reciprocable in a cylindrical cavity 77 for closing the valve. The head area of the piston 69 is exposed to tank pressures and the opposite end of the piston is provided with a valve land 78 engaging a seal 79 that defines a valve port of a lesser area than the piston head area. The piston valve 69 is urged to open position by a spring 85 and when open communication between the valve 79 and the tank 3 is established through a passage 86 provided in the side wall of the valve i911. It will be noted that the piston valve has a valve stem 87 which when the valve is closed extends into the cavity 67 where it can be contacted and displaced to open the piston valve 69 by upward movement of the valve stem 37a. When the valve port is open the passage 86 serves to prime the inlet of the pump '7 with liquid from the tank, and also serves as a moderate restrictor which causes a pressure drop that assists the piston in closing the valve port 79 if flow through the passage 68 is great enough to be indicative of a break, or, a fluid of lower vapor pressure is being dispensed from another tank by the pump 7.

On the other hand, if it becomes necessary to manually start the prime of the pump, the stem 37a will engage stem 87 after release of the locking ring 59 and positively open the piston valve 69 if the stem 87 is moved upwardly either by a pressure differential manually applied to the diaphragm 52 or by physical movement of the lower end 106 of the stem 37a upwardly.

In connection with the piston valve 69 closing when the pressure in the passage 60 therebelow is lower than in the tank pressure, reference is made to the companion valve shown in FIG. 2B where the stem 37b is a sleeve or tubular member having a longitudinal passage 88 therethrough which interconnects the chamber 8%} below the diaphragm through a lateral bleed opening 89 with the port side of a normally closed check valve 90 disposed in an enlarged head 92 at the top of the stem 37]). The head 92 of the stem 37 [2 includes 21 valves housing 92a threaded thereto that has a seal 921) at its lower marginal edge which seals against the upper edge 26d of the flanged collar 26b when the valve is closed. A normally closed check valve 90a is disposed in the valve head 14b in tandem with the check valve 90 whereby the two check valves together prevent downward passage of fluid to the chamber yet relieve to the tank any higher pressure that may develop in compartment 80 as when the diaphragm is moved downwardly by a higher pressure in chamber 50. Pressure in passage 60 higher than tank pressure can reach compartment 50 through the collar 46 and exert a downward pressure on the diaphragm 38 but this pressure cannot reach compartment 80 because a ball check valve 53a prevents relief through passage 53. On the other hand, in the event the pressure present in chamber 80 is above that present in passage 60 then the ball check valve 53a opens to relieve same to the pump intake.

In this connection reference is made to the dual tank system shown in FIG. 4A where the tank 3L is a low pressure tank having the valve 1B (FIG. 2B) connected thereto and the tank 3H is the high pressure tank having the valve 1A (FIG. 1A) connected to it. The respective passages 60 of the two valves are connected to a T-fitting 108 and the leg of the T-fitting is connected to the inlet 6 of the pump 7.

In this arrangement, the valves 83 are left closed and whenever it is desired to pump from one of the tanks the valve 83 connected thereto is opened and the pump is started whereupon that valve opens under pump output pressure as described and the other valve remains closed. If said other valve is valve 1A (FIG. 1A), it remains closed because the low pressure effective in its passage 60, upper chamber 50 and lower chamber 80 is not enough to overcome the higher tank pressure in tank 3H opposing the opening of the valve. If the other valve is valve 113 (FIG. 23), a higher pressure is present in its passage 69 than in tank 3L and the ball check valve 53a retains this pressure in its upper chamber 50 as already mentioned and thereby maintains the valve closed even though the higher pressure is also exerted on the valve itself and is urging it to open.

In some installations it is desirable to fill the tank 3 through the valve passage 60. In these instances a T-fitting 118 is installed in the inlet connection 6 for a direct connection to the filling device in a manner by-passing the pump 7. This fitting is plugged or capped as at 119 if not in use. For this purpose the plug 119 is removed and either one of two installations made depending upon the particular valve construction in use.

Preferably the valve shown in FIG. lA'is used in most installations and when it is desired to also fill the tank through the internal valve, a pressure equalizing line 111 of small pipe size is installed between the threaded opening 121 and a tank opening fitting 116 which can be located at the top or bottom of the tank. A back check valve 117 must be mounted in this line at the tank to allow pump pressure developed in chamber 50 to bleed back into the tank to avoid a build-up of pressure in chamber 50 which would tend to close valve 19.

Instead of the conduit 111 being used, the valve bodies 29 can be drilled as shown in FIG. to provide an in ternal bleed passage 36 and 36a. The passage 36 can be provided or extended as at 36a to the threaded opening 121 provided through the wall of chamber 50. Moreover, if desired the plug can be replaced with a dual acting valve if pressures are to be applied on both sides of the diaphragm 52. In which case, a dual acting valve arrangement (FIG. 5) is threaded therein and comprises a plug 122 having a cylindrical cavity 123 in the inner end thereof slidably receiving a piston sleeve valve element 124 therein sealed by an O-ring 125. The valve element 124 has a hex-shaped external contour 126 at its inner end shouldered to stop against the end of the plug in open position and faced off on its end face to close against a valve seat at 127. This controls the flow of replenishing or equalizing fiuid through conduit 36a to the chamber 50.

A Dill valve 128 is threaded into the valve end of the valve element 126 with its stern 129 exposed to contact with a removable pin 131 extending through a spider 132 in the plug at the bottom of a cavity 133 in its outer end and vented to atmosphere through lateral holes 134 in the sides thereof. Insertion and finger pressure on the head 135 of the pin 131 initially moves the piston sleeve valve 124 to its closed position to seal off conduit 36a and further movement of the pin opens the Dill valve 123 to vent chamber 50 to atmosphere through the spider 132 and vent holes 134. Thereupon the pressure in the chamber 89 below the diaphragm 52 opens the valve 19 for as long as the head 135 is manually depressed. When the pin 131 (and head) is released, the Dill valve closes, and pressure bleeding through the passage 36:: causes the piston sleeve valve 124 to open for quick application of tank pressure to the chamber 50 to close the valve 19 again if the pump is not running.

Furthermore, in connection with FIGS. 5 and 5A modi fications are shown in which the bleeder passage 53 (FIG. 2) can be eliminated and the chamber 50 can be vented to atmosphere through vents 134-and 134a so that the valve 19 can be opened independently of a pump 7 by the pressure present in the lower chamber 80. This will provide two results. It will liquid prime the passage 6t} by freeing vapor present below the valve 19 to bubble up into the tank 3, and with the valve 107 open (FIG. 1) liquid can be educted under continuous manual attention by gravity without the pump running.

Whenever the chamber 5!) is vented to atmosphere the use of the vent valve 161 (FIG. 1) or the handle 120 operates to vent chamber 80 to equalize pressures on opposite sides of the diaphragm whereby the spring 12 closes the valve 19.

In this connection it is to be noted that a V-seal 137 is provided below the bearing 47 which permits outflow of fluid from compartment 50 when the valve is open and prevents any inflow from the passage 60 when the compartment is vented to atmosphere.

In operation it will be observed that a hydraulic head is imposed upon the pump intake to maintain a pressure preventing vaporization or cavitation at the pump intake to assure a liquid solid condition throughout all conduits connected to the pump including the outlet up to a manual shut-01f valve 107. Then when the pump is started, the output pressure is forced up to a pressure much higher than the intake pressure and this is instantly effective in 14 the compartment whereupon the locking arm 62 or handle located at open position, the diaphragm, stem, and valve 1? are raised to their open position. Thereupon the manual shut-off valve 107 is opened for pumping operations to proceed. The valve 19 has little pressure drop and the pump intake continues its liquid solid prime. Thereafter the valve 19 is closed by venting pump output pressure in compartment 80 or by equalizing pressures on opposite sides of the diaphragm to an extent whereby the spring 12 is capable of closing the valve 19.

Consequently, it will be understood by those skilled in the art how the objects of the invention are attained and how various and further changes may be made in the valve system described without departing from the spirit of the invention, the scope of which is commensurate with the appended claims.

What is claimed is:

1. A liquid eduction device comprising a tank for storing liquefied gas in both its liquid and vapor phases, outlet means for said tank including a valve housing having a passage therethrough including a valve seat of the same size as the passage facing the tank in communication with said tank at the bottom thereof and subjected to the hydraulic head of the liquid in said tank in addition to the pressure of the vapor thereabove, a cap supported on said housing having valve inlet openings at the level of said valve seat, a valve head closing against said valve seat including a nonrotatable reciprocably supported by said housing and cap, means for closing the valve including a resilient member resiliently closing the valve means, said member being supported within said cap above said valve head, a liquid pump connected at its inlet to the passage and having an outlet, a bleed passage bypassing said valve head, pressure responsive means for reciprocating said valve stem including a diaphragm, means for applying to one side of the diaphragm liquid pressure from the output side of the pump to open said valve, bleed means for venting said liquid pressure to the other side of said diaphragm to close the valve head for reducing the pressure to below the tank pressure at said inlet openings, and conduit means for applying to the other side of the diaphragm liquid pressure from the tank to assist closure of the valve including a check valve opening in the direction of flow to the tank.

2. A liquid eduction device for a tank storing liquefied gas in both its liquid vapor phases comprising outlet means attachable to said tank including a valve housing having a valve seat facing the tank in communication with said tank at the bottom thereof and subjected to the hydraulic head of the liquid in said tank in addition to the pressure of the vapor thereon, a cap on said housing having openings to the tank at the level of said valve seat, a valve head closing against said valve seat including a stem reciprocably supported in said cap, means carried by said cap for closing the valve including a resilient element resiliently closing the valve head and a member operated by reciprocation of said stem for holding the valve head in closed position, a liquid pump connected at its inlet to the valve seat and having an outlet with -a shut-ofl' valve therein, means bypassing said valve head and seat for liquid priming of the pump inlet including a conduit through said head having a valve therein closing in the direction of flow of liquid from the tank through said conduit, the head of said valve being exposed in said -cap to the tank pressure applied thereto in a direction closing it, pressure responsive means for reciprocating said valve stem including a reciprocating member, means for applying to one side of the reciprocating member liquid pressure from the output side of the pump to open said valve, means for venting said liquid pressure, means for applying to the other side of the reciprocating member liquid pressure from the inlet of said pump to urge closure of the valve, and bleed means bypassing said reciprocating member tending to equalize liquid pressures on opposite sides of the reciprocating member.

3. A liquid eduction device for a tank storing liquefied gas in both its liquid and vapor phases comprising outlet means attachable to said tank including a valve housing having a valve seat facing the tank in communication with said tank at the bottom thereof and subjected to the hydraulic head of the liquid in said tank in addition to the pressure of the vapor thereon, a cap on said housing having openings at the level of said valve seat, a valve head closing against said valve seat including a stem reciprocably supported in said cap, means carried by said cap for closing the valve including a resilient element resiliently driving said stem for positively closing the valve head, a liquid pump connected at its inlet to the valve seat and having an outlet with a shut-off valve therein, pressure responsive means for reciprocating said valve stem including a reciprocating member, means for applying to one side of the reciprocating member liquid pressure from the output side of the pump to open said valve, means for applying to the other side of the reciprocating member liquid pressure from the inlet of said pump to urge closure of the valve, and bleed means bypassing said reciprocating member and said valve head tending to equalize liquid pressures on opposite sides of the reciprocating member including two check valves in tandem opening in the direction of flow of liquid from said one i side of the reciprocating member to the tank.

4. A quick acting cut-off filler-eduction valve for liquefied gas stored in both its liquid and vapor phases comprising a valve body defining a passageway having a valve seat therein in communication with liquid phase gas, a valve head closing against said seat and having a stem extending through the valve seat, resilient means urging said valve head to closed position, pressure differential responsive means including a reciprocating member connected to the valve stem, means for applying a pressure higher than that present in the passageway to one side of said pressure responsive means to urge it to open the valve, means assisting said resilient means for applying pressure in said passageway against the other side of said ressure responsive means to urge it to close the valve when said higher pressure drops below a predetermined differential between the two pressures, a bleed conduit bypassing said pressure responsive means including a check valve opening with flow from said one side to said other side of the pressure responsive means, and bleed means bypassing said reciprocating member for venting continuously said one side of said pressure responsive means to the tank including a normally closed valve opening with flow to the tank.

5. A quick acting cut-off filler-eduction valve comprising a valve body defining a passageway having a valve seat therein, a valve head closing against said seat and having a stem extending through the seat, resilient means urging said valve head to closed position, a bleed conduit bypassing said valve and valve seat for equalizing pressures on opposite sides thereof in their closed position including a normally open check valve closing in the direction of flow from the head to the valve seat, a pressure differential responsive means including a reciprocating member connected to the valve stem, means for applying a pressure higher than that present in the passageway to one side of said pressure responsive means to carry the valve stem into engagement with said check valve to open it when it is closed and to urge the stem to open the valve, means for applying pressure in said passageway against the other side of said pressure responsive means to urge it to close the valve when said higher pressure applying means ceases, bleed means interconnecting opposite sides of said pressure responsive means tending to equalize pressures on opposite sides thereof and, normally releasable means for locking said valve head in closed position closing said valve.

6. A quick acting cut-otl filler-cduclion valve comprising a valve body defining a passageway having a valve seat therein and inlet openings around said valve seat, a

valve head closing against said seat and rcciprocably receiving a stem extending through the seat, resilient means above said valve head urging said valve head to closed position, a bleed conduit bypassing said valve and valve seat to maintain said passageway liquid solid including a normally open check valve closable under tank pressure, pressure differential responsive means including a reciprocating member connected to the valve stem, means for applying a pressure higher than that present in the passageway to one side of said member actuating said stem in one direction to move the valve head to open position and move the check valve to open position when closed, means for applying a lower pressure against the other side of said member to urge it to close the valve when said higher pressure drops to a pressure equal to and less than said lower pressure.

7. A liquid eduction device comprising a tank for storing liquefied gas in both its liquid and vapor phases, outlet means for said tank including a valve housing having a valve seat facing the tank in communication with said tank at the bottom thereof and subjected to the hydraulic head of the liquid in said tank in addition to the pressure of the vapor thereon, a valve head closing against said valve seat, means for closing the valve including a resilient element resiliently closing the valve head, a liquid pump connected at its inlet to the valve seat and having an outlet with a shut-off valve therein, a bleed passage through said valve head for liquid priming of the pump inlet and including a check valve carried by said valve head closing in the direction of flow of liquid from said tank through said valve head, a valve stem movable in said valve head for engaging said check valve and valve head to open them when closed, pressure responsive means for recipro eating said valve stem, means for applying to one side of the pressure responsive means liquid pressure from the output side of the pump to open said valve including a pilot shut-off valve, means for venting said liquid pressure to the other side of the pressure responsive means, and means for applying to the other side of the pressure responsive means liquid pressure from the inlet of said pump to urge closure of the valve.

8. A liquid eduction device comprising a tank for storing liquefied gas in both its liquid and vapor phases, outlet means for said tank including a valve housing having a passage therethrough and a valve seat at the top of the passage facing the tank in communication with said tank at the bottom thereof and subjected to the hydraulic head of the liquid in said tank in addition to the pressure of the vapor thereon, a valve head closing against said valve seat including a stem, means for closing the valve including a resilient element resiliently closing the valve head, a liquid pump connected at its inlet to the passage and having an outlet with a shut-off valve therein, pressure responsive means for reciprocating said valve stem, means for applying to one side of the pressure responsive means a liquid pressure from the output side of the pump to open said valve, a bleed passage interconnecting the interior of the tank with said one side of the pressure responsive means to oppose opening of the valve including a normally closed check valve opening towards said tank, and a small passage bypassing said pressure responsive means for venting said one side of the pressure responsive means to permit opening of the valve.

9. A liquid eduction device comprising a tank for storing liquefied gas in both its liquid and vapor phases, outlet means for said tank including a valve housing having a passage therethrough and a valve seat of a predetermined area facing and in communication with said tank at the bottom thereof and subjected to the hydraulic head of the liquid in said tank in addition to the pressure of the vapor thereon, a valve head closing against said valve seat including a stem, means for closing the valve including a resilient element urging closure of the valve head, pressure differential responsive means including a reciprocating member connected to the valve stem and having a pressure responsive area greater than said predetermined area, means for applying pressure present in the passage to one side of said pressure responsive means to urge it to close the valve, means for applying to the other side of said pressure responsive means a pressure above said pressure in said passage to open the valve by said pressure responsive means, and means for venting said other side of said pressure responsive means to said one side to actuate said resilient element for closing said valve.

10. A liquefied gas supply system comprising separate tanks for storing liquefied gases having tWo different vapor pressures, a pump having an inlet and an outlet, outlet means for each tank including valve housings having outlet passage therethrough, means for connecting the outlets of said housings to the inlet of said pump, a valve in each of said housings closing in the direction of flow of fluid through said passage from the respective tanks, pressure responsive means in each housing including a reciprocating member for opening the respective valves, resilient means for closing the respective valves, connection means for selectively applying the output pressure of the pump to said reciprocating members for opening the valve selected, means for balancing pressures upon opposite sides of the one reciprocating member that is present in the one housing connected to said tank having the higher vapor pressure therein, and means for applying the pump inlet pressure to the other pressure responsive means on only the side thereof effective in the direction of closing the valve in the other one of said housings.

11. A liquid eduction device comprising a tank for storing liquefied gas in both its liquid and vapor phases, outlet means for said tank including a valve housing having a valve seat facing the tank in communication with said tank at the bottom thereof and subjected to the hydraulic head of the liquid in said tank in addition to the pressure in the tank of the vapor thereon, a valve member closing against said valve seat and including a reciprocable stem, means for closing the valve including an element resiliently urging the valve member to closed position, releasable means engaging said stem for positively holding said valve member in closed position, a liquid pump connected at its inlet to the valve seat and having an outlet with a shut-off valve therein, a passage bypassing said valve head and seat to interconnect the tank and inlet of the pump, pressure responsive means for reciprocating said valve stem including a diaphragm, means for applying to one side of the diaphragm liquid pressure from the output side of the pump to open said valve and including a shut-ofi valve, means for applying to the other side of the diaphragm liquid pressure from the inlet of said pump to urge closure of the valve, and venting means for reducing pressure upon said one side of the diaphragm comprising a bleed orifice passage connecting opposite sides of the diaphragm and including a check valve in said :bleed passage opening in the direction of flow of fluid from said one side to the other side of said diaphragmv 12. The combination called for in claim 11 in which said bypassing passage includes a normally closed check valve closing in the direction of flow of liquid from the tank to the inlet of the pump.

13. A liquid eduction device comprising a tank for storing liquefied gas in both its liquid and vapor phases, outlet means for said tank including a valve housing having a valve seat facing the tank in communication with said tank at the bottom thereof and subjected to the hydraulic head of the liquid in said tank in addition to the pressure in the tank of the vapor thereon, a valve member closing against said valve seat and including a reciprocable stem, means for closing the valve including an element resiliently urging the valve member to closed position, releasable means engaging said stem for positively holding said valve member in closed position, a liquid pump connected at its inlet to the valve seat and having an outlet With a shut-off valve therein, a passage 14 bypassing said valve head and seat to interconnect the tank and inlet of the pump including a normally open check valve in said valve head subjected to tank pressure and closing in the direction of flow of liquid from the tank, pressure responsive means for reciprocating said valve stem including a diaphragm, means for applying to one side of the diaphragm liquid pressure from the output side of the pump to open said valve and including a shut-off valve, means for applying to the other side of the diaphragm liquid pressure from the inlet of said pump to urge closure of the valve, and venting means for reducing pressure upon said one side of the diaphragm, comprising a bleed orifice passage connecting opposite sides of the diaphragm.

14. A liquid transfer valve for a tank storing liquefied gas in both its liquid and vapor phases comprising a valve housing connected to the tank and having a valve seat facing the tank in communication with said tank at the bottom thereof and subjected to the hydraulic head of the liquid in said tank in addition to the pressure in the tank of the vapor thereon, a valve member having a head closing against said valve seat and including a reciprocable stem, means for closing the valve including an element resiliently closing the valve member, a conduit through said head connecting opposite sides of the valve member including a normally open check valve closing in the direction of flow of liquid from the tank to the pump, piston means reciprocable in said head and exposed to tank pressure for closing said check valve, a liquid pump connected at its inlet to the valve seat and having an outlet with a shut-off valve therein, means responsive to pressure differentials for reciprocating said valve stem, means for applying to one side of the pressure responsive means liquid pressure from the tank to urge closure of the valve, means for applying to the other side of the pressure responsive means a pressure higher than said tank pressure to open said valve, and means for venting said higher pressure to close said valve by said tank pressure.

15. A liquid eduction device comprising a tank for storing liquefied gas in both its liquid and vapor phases, outlet means for said tan-k including a valve housing having a valve seat facing the tank in communication With said tank at the bottom thereof and subjected to the hydraulic head of the liquid in said tank in addition to the pressure in the tank of the vapor thereon, a valve member closing against said valve seat and including a stem reciprocably carried by the housing and valve member, means for closing the valve including an element resiliently closing the valve member and a manually releasable locking member operated with the reciprocation of said stem for positively holding the valve member closed at one limit of its movement, a liquid pump connected at its inlet to the valve seat and having an outlet with a shut-off valve therein, means bypassing said valve member and seat for liquid priming the inlet of the pump from the tank including a conduit through the valve head and a check valve in the conduit closing in the direction of flow of liquid through said conduit from the tank, said valve stem opening said check valve during its movement to its other limit of reciprocation opening said valve member, pressure responsive means for reciprocating said valve stem, means for applying to one side of the pressure responsive means the pressure from the output of the pump to open said valve and including a shut-off valve, manual means for releasing said locking member for releasing said valve member to move to its open position, and means for equalizing pressures on opposite sides of said pressure responsive means for said resilient element to urge closure of the valve for engagement of said locking member.

16. In a transfer system having a plurality of tanks for storing liquefied gas in both its liquid and vapor phases at different pressures therein a liquid eduction device for each tank comprising outlet means for said tank includ- 15 ing a valve housing having a valve seat facing the tank in communication with said tank at the bottom thereof and subjected to the hydraulic head of the liquid in said tank in addition to the pressure in the tank of the vapor thereon, a valve member closing against said valve seat and including a reciprocable stem, means for closing the valve including an element resiliently closing the valve member and a pressure responsive means including a reciprocable member for opening said valve, :1 liquid pump connected at its inlet to the valve seats of all valve housings and having an outlet with a shut-off valve therein, a bleed passage bypassing said valve head and seat in one of said housings for liquid priming of the pump inlet, means including shut-oil valves for selectively applying to one side of a selected reciprocable member liquid pressure from the outlet side of the pump to open its respective member, means for venting said applied liquid pressure to close said valve member, means for applying to the other side of the reciprocable member liquid pressure from the inlet of said pump to urge closure of all the valve members, bleed passage means bypassing said reciprocable members in all valves for equalizing pressures on opposite sides thereof, the bleed passage of the liquid eduction device connected to the tank having the lowest pressure having a back flow check valve therein confining said inlet pressure to said other side of the reciprocable member thereof.

References Cited UNITED STATES PATENTS 3,175,579 3/1965 Shaw "137-565 M. CARY NELSON, Primary Examiner.

ALLAN COHAN, Examiner.

W. CLINE Assistant Examiner. 

8. A LIQUID EDUCATION DEVICE COMPRISING A TANK FOR STORING LIQUEFIED GAS IN BOTH ITS LIQUID AND VAPOR PHASES, OUTLET MEANS FOR SAID TANK INCLUDING A VALVE HOUSING HAVING A PASSAGE THERETHROUGH AND A VALVE SEAT AT THE TOP OF THE PASSAGE FACING THE TANK IN COMMUNICATION WITH SAID TANK AT THE BOTTOM THEREOF AND SUBJECTED TO THE HYDRAULIC HEAD OF THE LIQUID IN SAID TANK IN ADDITION TO THE PRESSURE OF THE VAPOR THEREON, A VALVE HEAD CLOSING AGAINST SAID VALVE SEAT INCLUDING A STEM, MEANS FOR CLOSING THE VALVE INCLUDING A RESILIENT ELEMENT RESILIENTLY CLOSING THE VALVE HEAD, A LIQUID PUMP CONNECTED AT ITS INLET TO THE PASSAGE AND HAVING AN OUTLET WITH A SHUT-OFF VALVE THEREIN, PRESSURE RESPONSIVE MEANS FOR RECIPROCATING SAID VALVE STEM, MEANS FOR APPLYING TO ONE SIDE OF THE PRESSURE RESPONSIVE MEANS A LIQUID PRESSURE FROM THE OUTPUT SIDE OF THE PUMP TO OPEN SAID VALVE, A BLEED PASSAGE INTERCONNECTING THE INTERIOR OF THE TANK WITH SAID ONE SIDE OF THE PRESSURE RESPONSIVE MEANS TO OPPOSE OPENING OF THE VALVE INCLUDING A NORMALLY CLOSED CHECK VALVE OPENING TOWARDS SAID TANK, AND A SMALL PASSAGE BYPASSING SAID PRESSURE RESPONSIVE MEANS FOR VENTING SAID ONE SIDE OF THE PRESSURE RESPONSIVE MEANS TO PERMIT OPENING OF THE VALVE. 